Neuromuscular disorders in childhood: a descriptive epidemiological study from western Sweden

A retrospective epidemiological study of neuromuscular disorders was carrie d out in children born between 1979 and 1994 in western Sweden. The purpose was to determine overall and specific prevalences, overall cumulative inci dence and birth incidences of selected disorders. Cases were ascertained fr om 12 different sources and medical records, investigations and diagnosis w ere reviewed. We found point prevalence in the population <16 years of age of 63.1 x 10(-5) for all neuromuscular disorders and 53.1 x 10(-5) for inhe rited neuromuscular disorders. The point prevalence in children of school a ge was even higher. We found a higher occurrence of hereditary motor and se nsory neuropathy, congenital myopathies and mitochondrial encephalo-myopath y, a slightly lower occurrence of Duchenne muscular dystrophy and spinal mu scular atrophy and equal occurrence of myotonic dystrophy compared to previ ous studies in other countries. We conclude that neuromuscular disorders ar e more common in childhood than has previously been reported. (C) 2000 Else vier Science B.V. All rights reserved.